OK, that’s an exaggeration. There is nothing devastating about a 5-4 loss when you are already leading a best-of-five series, two-games-to-zero. Jose Lobaton’s walkoff splash blast into the fish tank Monday night against heretofore unhittable Koji Uehara probably will end up being a mere footnote in the Red Sox’ inevitable march to the 2013 World Series.

Still, it hurts. And it gives pause. This was a game with dozens of macabre twists and turns. And the Sox know they could be home today resting for Saturday’s ALCS opener at Fenway Park with the A’s or Tigers. They will try to close it out again Tuesday night, sending Jake Peavy to the mound in the Hampton Beach Casino of ballyards.

They know the series should be over. They led the Rays, 3-0 in the bottom of the fifth. They had 12-1 Clay Buchholz on the mound. It was going to be a sweep. The Sox were going to beat Tampa one more time and come home to get ready for the ALCS. But then things started to happen. The infamous Trop catwalks came into play. The Sox suddenly looked shaky on defense. Manager John Farrell opened himself up to criticism with a couple of bold moves and non-moves.

And the Rays seem to be able to reach down and find something extra every time they are on the brink of extinction. Monday’s victory was the Rays’ fourth elimination-game win in four cities over nine days.

The thriller in the Trop took four hours and 19 minutes. Twenty-seven position players and 11 pitchers participated. We saw a man with nine big league homers hit a home run against a man who hadn’t surrendered a home run since June 30.

Rays manager Joe Maddon went all National League on us, playing without his DH after the seventh inning. Farrell went for broke and then didn’t go for broke in the same inning. The Rays looked shaky in the field, just as they did in Boston. But this time the Sox also had bad moments on defense. In a couple of key spots, Mike Napoli looked like a catcher trying to play first base. Dustin Pedroia and Stephen Drew collided on a ball up the middle.

Boston’s troubles started in the fourth inning when a Ben Zobrist foul ball hit Catwalk B. An out turned into a walk and Buchholz was forced to throw 34 pitches to get out of the inning. In the bottom of the fifth, Evan Longoria hit a tying three-run homer off a weary Buchholz.

“We’ve been through a lot of stuff around here for the last several years,’’ said Maddon. “That ranks right up there with the best stuff, obviously. You can talk about the last game of the season, which has to be in some regards, but look at this whole week working up to today, and then this game is even more dramatic than the other games we had already won. It really is an incredible day for the Rays.’’

It was still 3-3 in the eighth when Farrell went for broke. Sort of. David Ortiz led with a walk and Farrell pulled him for a pinch runner. Quintin Berry immediately stole second.

But with two on and two out, Farrell allowed Drew to bat against lefty Jake McGee. Xander Bogaerts was available to hit for Drew. That is not going for broke.

“McGee has been dominant against righthanded batters,’’ said Farrell. “Stephen is a good fastball hitter. There was no hesitation to leave Stephen at the plate.’’

And in the ninth, with two outs and the score 4-4, Mike Carp batted in Ortiz’s spot and took a called third strike with Jacoby Ellsbury (eight hits in the three games) standing on third.

Ouch.

After two days of watching the Rays box the baseball around Fenway, the Sox were the ones who looked sloppy in the bottom of the eighth. With one on and one out, Desmond Jennings pushed a bunt to the right side. Napoli failed to stay home and there was nobody to cover first when Franklin Morales gloved the bunt. Then Pedroia inadvertently blocked Drew on a grounder up the middle. With the bases loaded, Delmon Young hit a grounder to Napoli and the first baseman was unable to make a play at home. Tampa scored the go-ahead run on the play.

After the Sox rallied to tie it off Fernando Rodney in the top of the ninth, Lobaton came up with two out and nobody aboard and found the fish tank in right-center. Ballgame.

“I can’t say enough, the way we came back after giving up the lead,’’ said Farrell. “Just an exciting game. Well-played game. Still, we played a very good game tonight.’’

Perhaps. But it doesn’t feel good at this moment. This was the Red Sox’ first postseason walkoff loss since the Aaron Boone/Grady Little game of 2003.